16.6 Types of Data Transfers

Based on the memory access capabilities of the DMA (see Table 16-1), the following sections discuss the different types of data movement between the source and destination memory regions.

• N:1

  This type of transfer is common when sending predefined data packets (such as strings) through a single interface point (such as communications modules transmit registers).

• N:N

  This type of transfer is useful for moving information out of the program Flash or Data EEPROM to SRAM for manipulation by the CPU or other peripherals.

• 1:1

  This type of transfer is common when bridging two different modules data streams together (communications bridge).

• 1:N

  This type of transfer is useful for moving information from a single data source into a memory buffer (communications receive registers).